Research center in universities, that some times need to use software for research that is only officially supported in RHEL but that does not have money to keep RHEL licenses.

One of the original RHEL clones was Scientific Linux that was maintained by those organizations for their use.

They dropped because CentOS better at the time and they were doubling effort for something that was already available.

Probably a different group of people, now. The original purpose was "RHEL clone". Now it is "RHEL-like LTS distribution," somewhere mid-stream between CentOS Stream and RHEL.

Alma Linux was much faster at releasing updates than Rocky. Alma also had secure boot working on their first release, whereas Rocky didn’t.

That’s why I favored it. Alma seemed to have more robust infrastructure and processes in place looking from the outside.

Alma used CloudLinux's secure boot key (among other CloudLinux infrastructure / resources) for their first few releases.

Rocky Linux didn't have secure boot out the gate because we built everything from scratch, which included going through the long process of getting our own secure boot key approved / signed by Microsoft. See https://github.com/rhboot/shim-review/issues/194 (Alma didn't get their own until https://github.com/rhboot/shim-review/issues/235)

Alma also has a live ISO.

Rocky Linux has a large selection of live ISOs in different flavor desktop environments / etc at https://rockylinux.org/alternative-images

I help run a (small) HPC at a research institute and know a lot of groups in our community who run alma on their nodes. We went with rocky because we flipped a coin

Wasn’t Alma originally a collaborative effort between several university affiliated scientific labs?

You're thinking of Scientific Linux.

cPanel mostly, so 70% of the web hosting industry. So "the Internet"